The invention relates to an electromechanical steering system for a vehicle.
DE-A1-1972853 discloses such an electromechanical steering system. For supporting the steering moment produced by the driver, the steering system has an additional system, which is driven by an electric motor and acts on the steering shaft of the steering system and meshes with the steering shaft over a worm gear, as a result of which an additional moment, supporting the steering motion of the driver, can be introduced into the steering shaft. In order to obtain information about the steering angle and the steering angle speed, a steering angle sensor, the signals of which are transferred by a coil spring to a control device in the housing, is provided on the steering shaft. The coil spring is located in a coil spring housing and is connected at one end with the sensor, rotating with the steering shaft, and, at the other, with a socket attached to the housing, over which an electrical contact to the steering device can be produced. The coil spring is in a position to carry out, without damage, the steering shaft rotations occurring during the driving operation.
The coil spring housing with the coil spring disposed therein described in DE-A1-19228513 is located in an accommodating space within a steering housing, in which the steering shaft is mounted rotatably. The worm gear, which transfers the rotational movement of the electric motor to the steering shaft for supporting the steering movement, is located in the accommodating space in the steering housing. So as to prevent contamination of the sensor or of the contact sites of the sensor or of a magnet assigned to the sensor by the lubricating grease of the worm gear, a partition is provided there, which divides the accommodating space into a section, which accommodates the coil spring, and a section, which accommodates the transmission. The housing of the coil spring forms a part of this partition.
The DE-A1 197 55 094 also discloses such an electromechanical steering system.
The coil spring housing with the coil spring disposed therein is located in an accommodating space within a steering housing, in which the steering shaft is mounted rotatably. The worm gear, which transfers the rotational movement of the electric motor to the steering shaft for supporting the steering movement, is located in the accommodating space in the steering housing. It is necessary to pay attention so that the sensor or the contact sites of the sensor or a magnet, assigned to the sensor, are not contaminated by the lubricating grease of the worm gear. In addition, the coil springs, including the coil spring housing and the steering angle sensor, also represent a source of danger for the worm gear, since the latter can be blocked in the event that a component within the accommodating space becomes detached or breaks off.